/etc/sysctl.conf

# This fix enoumous big diry bytes (16 gb system vm.dirty_background_bytes 3.2 Gb ??? )
# 64  mb - when system starts writing to disk  64*1024*1024
# 256 mb - when system limits io to device speed 256*1024*1024
# Guys from SUSE recommends keep this in proportion 1:2 - 1:4
# Ubuntu guys recommends to set this even lower 16 and 42 Mb but well...
# This emulates near 1 gb ram default behaviour

#let only 64 mb of pages in ram before writing to disk on background
vm.dirty_bytes = 67108864
#let only 256 mb of pages in ram before blocking i/o to write to disk
vm.dirty_background_bytes = 268435456

## use this on low ram machile (32 and 64 mb)
#vm.dirty_bytes = 33554432
#vm.dirty_background_bytes = 67108864